Three way slide valve with center return

Abstract

A three way slide valve includes a rectangular valve slide fitted into a housing formed of two halves having mating flat surfaces. Each housing half is recessed to provide a chamber for the valve slide and also a spring chamber which restrains both ends of a double acting return spring. One end of the return spring engages one end of the valve slide and the other part of the spring engages a loop on the valve slide for return to center action. Ports in the housing halves are provided with shear seals in engagement with the valve slide.

I claim: 
     
       1. In a valve mechanism, a valve housing formed of two moulded housing parts joined together, said housing parts defining a slide valve chamber, a slide valve member in said chamber, operating means for the slide valve member extending through one end of said housing, a threaded mounting stud for the housing through which said operating means extends, a portion of said stud being formed on one housing part and another portion of the stud being formed on the other housing part, said housing parts being separable and joined together after installation of the slide valve member. 
     
     
       2. A valve mechanism as defined in claim 1 in which the two housing parts have flat mating surfaces, and valve ports cooperating with flat valving surfaces on the slide valve member. 
     
     
       3. A valve mechanism as defined in claim 1 in which the two housing parts have elongated mating surfaces and are joined together by a pair of fastening means, said fastening being on opposite sides of the slide valve member and located at a point causing substantial portions of the mating surfaces to extend beyond the fastening means in each direction, enabling said pair of fastening means to be the sole means holding the housing parts together. 
     
     
       4. In a valve mechanism, a valve housing having a slide valve chamber and an adjoining spring chamber of larger cross-section than the slide valve chamber providing a shoulder at the junction of the spring chamber with the slide valve chamber, slide valve member means movably mounted in the slide valve chamber and having a rectangular portion adjacent to the spring chamber, said valve housing being formed of two parts contacting opposite faces of the slide valve member means, said housing parts having elongated mating surfaces and cooperating to form the slide valve chamber said valve housing being formed with at least one valve port controlled by the slide valve member means, said valve housing also being formed with an opening at one end leading from the slide valve chamber to the outside of the housing, and the slide valve member means including operating means passing through said opening for operating the slide valve member means from outside the housing, spring means in the spring chamber arranged to engage the rectangular portion of the slide valve member means and said shoulder, said spring means urging the slide valve means in a predetermined direction and being stopped by the shoulder, said spring chamber being located in the housing between the valve port and the opening for the operating means. 
     
     
       5. The combination recited in claim 4 in which the slide valve member means is a single integral member having a valve passage inside the housing and extending through the opening in the housing to outside the housing. 
     
     
       6. The combination recited in claim 4 in which a pair of fastening means secures said housing parts together, said fastening means being on opposite sides of the slide valve member means, said fastening means also being located between the valve port and the open end of the housing, causing substantial portions of the housing part mating surfaces to extend beyond the fastening means in each direction, enabling said pair of fastening means to be the sole means holding the housing parts together.